Process fob treating hydrocarbons



1936- L. KlRSCHBRAUN'- Re. 19,818

PROCESS FOR TREATING HYDROCARBONS bri inal Filed Nov. 1, 1922 Fifi/m Idikness: .Ziu/Frt for:

Reicsued Jan. 7, 1936 v UNITED "STATES PATENT OFFICE 19,818 raocnss roa TREATING maocanaons Lester Kirschbraun, Leonia, N. 1., assignor to Universal Oil Products CompanmChi'cago, Ill., a corporation oi South Dakota Original No. 1,824,215, dated September 22, 1931, Serial No. 598,248, November 1, 1922. Renewed November 25, 1929. Application for reissue September 15, 1932, Serial No. 633,372

19 Claims. (01. 196-49) pansion chamber 3 by means oi the transier line a l in which is interposed a throttle valve 5. .The transfer line 4 is connected as shown at 6 to the upper end oi the expansion chamber and there the heated oil is delivered into the conical cham- 1 her 1, formed by the conical shell 3, the arrangement being such that the shell 3, which is shown, opens outwardly towards its lower end and the velocity oi the vapors is reduced as they pass irom the top oi the expansion chamber 3 to the lower end thereoi. The lower, end of this suspended conical shell 3 is provided with an upturned rim 9 iorming a channel portion. As the oil passesdown through the chamber 3, the residue or unvaporized portions will drop out and iall through the open-ended fines or tubes l3 supported between the plates H and I2. The vapors will pass up around the channel 3 and inclined circumierentially extending bailles i3, 23 and 2| and then out through the vapor pipe it having a throttle valve l5 to the condenser coil l3 and thence to the receiving drum II, which drum I1 is provided with gas outlet valve I8 and distillate drawofi valve l3.

The heavier vapors will condense in the upper part oi the expansion chamber 3 outside oi the cone, provided with the baflies 23 and 2| and the aerial condenser pipe ll (there may be a plurality .01 these if desired), or any other suitable iorm of aerial condenser used. The reflux condensate will be caught in the channel 3, drawn of! through the pipe 23 having throttle valve 24 to the pipe 25, which is connected to the inlet side of the heating coil 2. This reflux condensate, of course, will be relatively hot.

The raw oil to be treated comes from any suitthe chamber 23 iormed by the plate l2 and bot-' tom plate 30 and thence by residue drawofl pipe 3|, having valve ,32 to a still 33, which may or may not-be heated. It is contemplated that in the still 33, the pressure, it desired, may be ma- 5 terially reduced relative to the pressure inithe expansion chamber 3, which will permit the residue to readily distill because oi the reduction of pressure. The vapors may then pass out through vapor pipe 34 having throttle valve 35 to con- 10 denser coil 35 and thence to receiver 31. Here the distillate, collected in receiver 31, may. be

drawn off through pipe 33 backto the pump 26,

and can be rerun through the system;

In carrying out the process, the pressure on the 15 heating coil, expansion chamber and receiver Il may be say, 200 pounds, and the pressure on the still 33 reduced to say, pounds. The oil-may be heated to a temperature in the coil oi say, 800 degs. F. Or the invention may be carried out by 20 having a pressure oi say, 300 pounds on, the heating coil 2, 200 pounds on the expansion chamber 3, and 50 pounds on the still 33. In this case a pump. should be introduced into the line 23 to iorce the hot reflux condensate back into the coil 2 or such reflux condensate may be taken elsewhere to be treated or such reflux condensate may be delivered into the still 33, by closing valve 23 thus obviating the necessity of a pump.

In its broader aspects, the invention is not 30 limited to the particular place from which the reflux condensate is drawn or any particular pressure on any part of the apparatus except that it would be desirable to have a higher pressure on the expansion chamber 3 than on the still 5 33. As a result of the process and apparatus here shown, less difliculty with carbon will be encoun-' tered, thus permitting a greater percentage of the oil to be taken over as pressure distillate and also reducing to aminimum the precipitation of car- 40 him in the reaction zone. This results from the fact that the oil going down through the cone referred to, more or less in the'iorm of a spray, finds no placeon which to deposit the carbon containing tar until the tar meets the upper end 45 of the relatively cold tubes. Here the tar passes through these tubes and is immediately reduced. in temperature sufliciently to prevent further de-' composition; then flows into the lower chamber 29 and is immediately drawn out of the system. 50.

It is to be understood that there is a whole nest oi these tubes, probably, for example, several hundredsuflicient to insure a maximum surface opening in the upper plate while at the same time allowing suflicient space between the tubes for the crude oil to pass'by and cool them. The

arrangement is preferably such as to reduce to..

a minimum the horizontal surface on which any carbon might deposit and to insure any liquid tar immediately flowing out.

With reference to the residue which is cooled in passing through the tubes l0, it is advantageous to prevent the collection of any substantial accumulation of heated liquid in these tubes, and the cooled residue should be transferred out of the chamber 29 as soon as possible. This, of course, can be governed somewhat by the size and length of the cooling tubes, which cooling tubes may be from 1" or 2" in diameter to say, 6" or more, and the length of the tubes from a few feet to 8' or 10' or more. It is to be understood that the size of the tubes will depend on the general construction of the apparatus. It is understood that the apparatus should be equipped with the usual manholes and other means for cleaning and the usual pyrometers, pressure gauges through said reaction zone, while out of contact with the downflowing oil, in collecting condensate separated from the vapors rising in said annular stream and in removing the same from said reaction zone, without permitting the same to contact with unvaporize'd oil therein, and in returning such condensate to said heating zone, in taking off uncondenscd vapors irom said reaction zone and in subjecting the same to condensation, and in collecting the resulting distillate.

2. A continuous process for cracking hydrocarbon oil, consisting in raising the .oil to a cracking heat while advancing in a restricted stream through a heating zone, in introducing the heated oil to the top of an enlarged reaction zone, to flow downwardly through the central portion thereof, in passing vapors released from the oil in said reaction zone upwardly through the reaction zone in an annular stream, out of contact with the downflowing oil, in collecting condensate separated from the vapors in said annular stream and in removing such condensate from said reaction zone, without permitting the same to commingle with unvaporized oil in the reaction zone, in passing a stream of charging oil in heat interchange relationship with unvaporized oil in said reaction zone and in subsequently uniting the charging oil with the condensate which has been removed from the reaction zone, and in supplying the resulting commingled oils to said heating zone, to form the stream advancing therethrough.

3. In processes for cracking high boiling point oils to produce low boiling point oils in which the oil is subjected to pressure distillation in a pressure distillation zone, the pressure distillation zone comprising heating and reaction zones, the

oil being pused flrst through the heating zone' I the residue is eiiected at the temperature to which said residue has been cooled, and returning products obtained by said distillation of the residue to said pressure distillation zone.

4. In processes for cracking high boiling point 10 oils to produce low boiling point oils in which the oil is subjected to pressure distillation in a pressure distillation zone, the pressure distillation zone comprising heating and reaction zones, the oil being passed first through the heating zone 15 and thence delivered to the reaction zone, vapors and unvaporized oil separately removed from the reaction zone, the vapors subjected to reflux condensation to separate insufllciently cracked fractions, the improvement which comprises preclud- 20 ing the accumulation of unvaporized residue in the reaction zone by removing the residue therefrom as rapidly as formed, cooling the residue as it is removed from the reaction zone while under pressure by heat exchange with incoming charg- 25 ing oil for the process, thence delivering the residue to a zone of lower pressure wherein distillation of theresidue is effected at the temperature to which said residue has been cooled, and returning products obtained by .said distillation 30 of the residue to said pressure distillation zone.

5. The process of cracking petroleum oils which comprises continuously passing the oil in a restricted stream through a zone wherein the oil is heated to a cracking temperature, thence de- 35 livering this restricted stream of oil constituents into a reaction zone, continuously removing vapors, and liquid oil from said reaction zone without permitting the liquid oil so removed to mingle with the oil of said restricted stream, effecting 40 the removal of the liquid oil at a rate adequate to prevent during normal operation of the process the accumulation of any appreciable body of oil in such reaction zone, subjecting the vapors evolved from the oil to reflux condensation, re- 45 turning reflux condensate thus derived to said restricted stream, maintaining a substantial superatmospheric pressure on the oil in said restricted stream and reaction zone, partially cooling the liquid oil removed from said reaction zone 50 to prevent further decomposition and vaporizing from the removed oil by its contained heat a recycle stock by effecting distillation thereof in a zone maintained under lower pressure than said reaction zone, and returning the recycle stock to 55 the cracking process.

6. The process of cracking petroleum oils which comprises continuously passing the oil in a restricted stream through a zone wherein the oil is heated to a cracking temperature, thence deliv- 60 ering this restricted stream .of oil constituents into a reaction zone, continuously removing vapors, and liquid oil from said reaction zone without permitting the liquid oil so removed to mingle with the oil of said restricted stream, effecting the removal of the liquid oil at a rate adequate to prevent during normal operation of the proces the accumulation of any appreciable body of oil in such reaction zone, maintaining a substantial superatmospheric pressure on the oil in said 70 restricted stream and reaction zone, partially cooling the liquid oil removed from said reaction zone to prevent further decomposition and vaporizing from the removed oil by its contained heat a recycle stock by eflecting distillation there- I 01' in a zone maintaired under lower than said reaction zone, and returning the recycle stock to the cracking process.

'7. A process of cracking hydrocarbon oil which comprises heating the oil 'to cracking temperature as it flows under superatmospheric pressure through a heated coil, passing the oil thence into an enlarged reaction chambermaintained under superatmospheric pressure wherein separation of vapors and liquid occurs, removing the separated vapors, withdrawing liquid from said enlarged chamber at a rate adequate to prevent accumulation oi liquid therein and expanding the liquid thus withdrawn directly into a flash chamber and effecting distillation by means 01' the contained heat of saidliquid underv reduced pressure.

8. A process of cracking hydrocarbon oil which comprises subjecting the oil to cracking temperature under superatmospheric pressure as it flows through a heated coil, passing the oil thence into an enlarged reaction chamber wherein without any material reduction in pressure separation of it flows through a heated coil, is passed thence into an enlarged reaction chamber from which va ors and liquid are separately removed and return of the latter to said coil prevented and the vapors subjected to fractionation to form a condensate which is returned to the heating coil, the process that comprises. withdrawing the liquid from said enlarged reaction chamber at a rate adequate to prevent accumulation of liquid there- 'in and expanding the liquid thus withdrawn di- 7 rectly into a-flash-chamber and efiecting distillation by means of the contained heat of said liquid under reduced pressure.

10. A process of cracking hydrocarbon oil which comprises heating the oil to cracking temperature as it flows under superatmosphe'ric pressure through a. heated coil introducing the heated oil into the top of an enlarged reaction chamber maintained under superatmospheric' pressure wherein separation of vapors and liquid occurs, removing the separated vapors, withdrawing the precipitated liquid from the bottom of said enlarged chamber at a point remote from that of the introduction or the oil to the chamber and at arateadequate to prevent accumulation of liquid therein and expanding the liquid thus with drawn directly into a flash chamber and effecting distillation by means 01 the contained heat of said liquid under reduced pressure.

11. A process of cracking hydrocarbon oil which comprises heating the oil to cracking temperature as it flows under superatmospheric pressure through a heated coil, passing the oil thence into an enlarged reaction chamber maintained under superatmospheric' pressure wherein separation of vapors and liquid occurs, removing the separated vapors withdrawing liquid from said enlarged chamber at a rate adequate to prevent accumulation of liquid therein and expanding the liquid thus withdrawn into a flash chamber and eilecting distillation by means of the contained heat of said liquid under reduced pressure.

12. A process of cracking hydrocarbon oil which comprises subjecting the oil to cracking temperature under superatmospheric pressure as it flows through a heated coil, passing the oil thence into an enlarged reaction chamber wherein without any material reduction in pressure a flash chamber and efiecting distillation by 10 means of the contained heat of said liquid under reduced pressure.

13. A process of cracking hydrocarbon oil wherein the oil is raised to a cracking temperature as it flows through a heated coil, is passed thence into an enlarged reaction chamber from which vapors and liquids are separately removed and return of the latter to said coil prevented and the vapors subjected to fractionation to form a condensate which is returned to the heating coil, the process that comprises withdrawing the liquid from said enlarged reaction chamber at a rate adequate to prevent accumulation of liquid therein and expanding the liquid thus withdrawn into a flash chamber and efiecting distillation by means of the contained heat of the liquid under reduced pressure.

14. A process of cracking oil which comprises heating hydrocarbon oil to cracking temperature under pressure in a long heating coil to heat the oil extensively while flowing the oil through said coil at a rapid rate, passing the heated oil into the upper portion of an enlarged zone to eiiect the separation of the light cracked products by distillation, removing the separated vapors, separately withdrawing the liquid from said enlarged zone at a rate adequate to prevent accumulation of substantially any oil therein, stripping the lighter fractions of the discharged residual oil by, suddenly expanding it at low 49 pressure into a flash chamber where substantial vaporization by its contained heat takes place and withdrawing residual oil from the bottom of said flash chamber.

-15. A process of cracking oil which comprises charging a stream of hydrocarbon oil once through a cracking coil maintained under cracking temperature and pressure, curtailing undesirable cracking of liquid constituents and separating the light cracked products by delivering 50 the heated oil into an enlarged chamber where no substantial accumulation of liquid oil is permitted, the residual oil being rapidly discharged therefrom and from the cracking system to prevent accumulation of liquid in said chamber,

removing the vapors iromsald chamber, separating out the heavier constituents thereof by partial condensation, expanding the discharged residual oil at low pressure into a flash chamber to vaporize the lighter constituents by the introducing the preheated mixture and the hot condensate from said. initial partial condensation into the coil to be heated therein.

16. A process of cracking oil which comprises heating to cracking temperature a stream of hydrocarbon charging oil, mixed only with clean condensate produced in the process, to the desired extent as it flows under pressure through a heating coil, delivering the efliux from said coil without material pressure reduction into an enlarged unheated chamber where vaporization takes place and accumulation of liquid is substantially preventedby the rapid and continuous discharge oi residual oil therefrom at such a rate as to prevent said residual oil from remaining in the chamber for a sufllcient length of time to permit the formation of carbon therein, reducing the pressure materially on the discharged residual oil and distilling it under its contained a heat to leave a liquid residue, subjecting the 1o ing vapors and liquid oil from said enlarged zone without permitting the liquid oil so removed to mingle with the oil of said restricted stream, efiectingthe removal of the liquid oil at a rate adequate to prevent, during normal operation of the process, the accumulation of any appreciable body of oil in said enlarged zone, expanding the liquid oil thus removed into a flash chamber, and efl'ecting distillation by means 01' the contained heat of said liquid under reduced pressure.

18. A process of cracking hydrocarbon oil which comprises'heating the oil to cracking ternperature as it flows under super-atmospheric pressure through a heating coil, passing the oil thence into an enlarged reaction chamber maintained under superatmospheric pressure wherein separation ot vapors and liquid occurs, removing 5 the separated vapors, withdrawing liquid from said enlarged chamber at a rate adequate to prevent any substantial accumulation oi liquid therein, expanding the liquid thus withdrawn into a flash chamber, and eflecting distillation by means of the contained heat 01' said liquid under reduced pressure.

19. The process of cracking petroleum oil which comprises continuously passing the oil through a heating zone wherein the oil is heated to a cracking temperature, thence passing the heated oil to a reaction zone through which liquid oil passes in continuous flow and at such a rate that no substantial accumulation of liquid oil occurs therein, thence partially cooling the oil discharging from said reaction zone to substantially check the cracking reaction, passing the partially cooled oil at its reduced temperature immediately into a flash chamber, eil'ecting vaporization and separation from the liquid oil, by latent heat distillation .in the flash chamber, of a re-cycled stock, removing and condensing vapoi-s liberated from the liquid oil in said flashed vapor, and returning condensate thus derived as a re-cycled stock to said heating zone. so

LESTER KERSCHBRAUN. 

